Protests in both Algeria and Yemen threaten to bring down the ruling governments as occurred in Egypt and Tunisia.

On Sunday, hundreds of anti-government protesters marched toward a presidential palace in Sana'a, Yemen, calling for the ruler, President Ali Abdullah Saleh, to quit. In Algiers, violent clashes and continuing protests have led President Abdelaziz Bouteflika to announce governmental changes.

Some of the Yemeni protestors chanted, "First Mubarak, now Ali," ominously referring to Hosni Mubarak, who recently resigned as president of Egypt, and Saleh, who has been power for 32 years. The protests were organized largely via text messages, and were the largest yet by Yemenis in three days of unrest. Saleh, who has ruled Yemen for 32 years, pledged after the initial wave of protests not to stand for re-election when his current term ends in 2013.

Since Mubarak resigned as president of Egypt on Friday, police officers have filled Sanaa's central square, which, just like in Cairo, is called Tahrir Square.

The protesters on Sunday were mostly younger Yemenis, who said that the deal between Saleh and the organized opposition was not good enough, and demanded that Saleh step down immediately.

Algeria, Too
In Algeria, too, thousands of specially-protected policemen filled the capital on Saturday in an effort to prevent mass protests. At least 12 people were arrested, and protestors and police forces clashed violently. The protestors chanted, Bouteflika Go Home!, referring to President Abdelaziz Bouteflika, who has been in office since 1999 and has continued the country's emergency rule that has been in effect since 1992.

As protests continued Sunday and Monday, Bouteflika’s government rushed to announce on Monday that it would end the state of emergency, and would implement other major governmental changes as well.

In the Sana'a protests, security forces blocked the protesters' path about three kilometers from the palace. CNN reports that the situation then intensified, with protesters attempting to reach the palace via side streets and clashing with police. Tawakkol Karman, a rights activist and president of Women Journalists Without Chains, told the news network that anti-riot police "went into the crowd of protesters with batons and tasers," that they hit her and other protesters with sticks, and that at least 12 people were arrested.

The CNN crew at the scene reported that it was surrounded by security officers, who seized its videotapes. Meanwhile, about 40 pro-government demonstrators chanted their support for Ali nearby.

Sheik Hamid al-Ahmar, an opposition leader, told the New York Times on Sunday that political leaders had tried to prevent the younger demonstrators from taking to the streets. He said that the older leaders wanted to "move more slowly," but voiced support for the new protests nonetheless.

State-run news agency Saba reported that Saleh had decided to postpone a planned visit to the United States that was scheduled for later in the month.